الفهرس 
NanotechnologyOnly 14 pages are availabe for public view
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Abstract
Because of its interesting properties, Cu has recently received great
interest in a variety of industrial fields, including electrical communications in
electronics, machinery, civil engineering, automobiles, and other important
industrial applications. Among these outstanding properties are its high
thermal and electrical conductivity. In contrast, the main disadvantages of Cu
are its poor mechanical properties, high thermal expansion coefficient (CTE)
value, and low wear resistance, which limit its technological applications. As
a result, this thesis aims to improve the aforementioned properties of Cu by
preparing Cu-based nanocomposites enhanced with hybrid ceramics in the
nanometer range. Three groups of nanocomposites were prepared, optimized
with different proportions of SiC-FA, FA-Gr, and SiC-Gr, respectively, using
the powder metallurgy method. The percentages of SiC and FA added varied
at 0, 1, 2, 4, and 8 volume percentage, while Gr was added at 0, 0.1, 0.2, 0.4,
and 0.8 volume percentages. The Cu based hybrid nanocomposites were
prepared in two stages. The first is mixing and milling the nanocomposite
powders in a high-energy ball mill for 20 hours at a speed of 440 rpm. The
second stage is pressing the prepared powders at a pressure of 30 MPa and
sintering them at 700, 800, and 850 °C for one hour in an argon atmosphere.
XRD and TEM analyses were used to examine the phase changes of milled
powders and particle properties (shape and size), and the microstructure of the
sintered nanocomposites was tested by FESEM. The physical properties (bulk
density, relative density, and apparent porosity) and mechanical properties,
including microhardness, compression test, and elastic modulus (using
ultrasound technology), were also measured for the sintered nanocomposites.
In addition, thermal expansion